Today, China's borders are wide open. Almost anybody who wants a passport can get one. And Chinese nationals are leaving in vast waves: Last year, more than 100 million outbound travelers crossed the frontiers.

Most are tourists who come home. But rapidly growing numbers are college students and the wealthy, and many of them stay away for good. A survey by the Shanghai research firm Hurun Report shows that 64% of China's rich?defined as those with assets of more than $1.6 million?are either emigrating or planning to.

The decision to go is often a mix of push and pull. The elite are discovering that they can buy a comfortable lifestyle at surprisingly affordable prices in places such as California and the Australian Gold Coast, while no amount of money can purchase an escape in China from the immense problems afflicting its urban society: pollution, food safety, a broken education system.